A thing that really impressed me in Nox, and which I have never seen this far, was the line of black powder on the floor … leading to a heavy stone one wouldn't have been able to "lift" otherwise … Fire on the one end - I could really see the flame following the "powder-line" ! - kaboom on the other side !

If you happen to make this true as well …

But I think it could be difficult to implement …

What about bringing trees down do block a road ? Would the enemies be hindered ? If so, in how far ?
Would they be able to climb that fallen tree in order to jump over it - or just run around it ?

Another, really weird thing would be to place a really beautifully looking statue on the way … With an enemy slowing down, with the desire to rather stop and adore the statue than follow his or her foe …

A really dangerous thing would be fire in general. Light a branch which has been chopped off a tree, and throw this burning branch … making fire damage or so …

Or what about rolling things ? Rolling Stones ( ) and logs …

In the demo I saw a new kind of "trap" : Marbles … put down on the floor … With the result of the enemy having to do a check of a talent I forgot, or the enemy will fall down … Like in nature … - Well, I could imagine this with pebbles, too …